How do you know he didn't mean that production costs are down TO 70%? And how do we know he wasn't referring to some other costs? It seems a little weird that production costs would have dropped that much in six months (IIRC, Sony was losing $40 per console in 12/08).
I think those who are expecting a price cut and/or a slim are in for a big letdown (surprise, surprise). It's very possible that the exec misspoke, was misquoted, or was misinterpreted. In any case, any evidence for a price cut and/or slim is circumstantial, at best. Even if they release a slim, I doubt it will cost less than the current phat.
Maybe I just don't like to get my hopes up, but I also think it's best to remain skeptical (of ALL things, not just prices of video game consoles).